Thanduil was given this scroll by Chloe in the general store in Fairmyr.

“Funny you should be asking that.” She says in reply to Thanduil’s question, “All the magic we found was either sold, or taken by our sorcerer who had a liking for anything arcane, whether he could use it or not. He left one scroll though. He said that the text of the spell is wrong, total gibberish. Not only that, but someone has scrawled all over the front of it.” She passes Thanduil a battered and stained sheet of parchment.